Windows Anytime Upgrade will only work with a Retail/Retail Upgrades including MSDN/Dreamspark Premium product keys. It will not work OEM keys.
Press [Windows] and [Pause|Break] or go to Start, right click the computer and select properties. This screen will list:
- Windows Edition
- Service Pack
- Architecture (32 or 64 Bit)
- Windows Activation Status
- Product ID
Ensure Windows is activated, in this case the base install is a Dell Windows 7 Home Premium OEM license identified by the product ID.
To upgrade left click "Get Features with a New Edition of Windows". Select Enter an Upgrade Key.
You will no longer be able to buy a Retail Windows 7 Upgrade key.
Input your product key and select next. In my case I entered a Dreamspark Premium Product Key.
Windows will verify the key.
If the key is valid you will get a screen telling you about the license agreement. Select I accept:
Windows will begin the upgrade and download some updates:
When its ready it will automatically restart and you will get a screen saying "Upgrading Windows". After you log in you will be presented with the following screen. Select close:
Press [Windows] and [Pause|Break] or go to Start, right click the computer and select properties. Your new Edition of Windows should now be listed and your product ID should be changed. Note it is not OEM anymore but it is a Dreamspark Premium key.
Windows is however not activated. Select Activate Windows Now.
Select Activate Windows Online Now.
Hopefully it says activation was successful. If so select close:
If its not activated use Phone Activation.
You should now have your activated upgraded Edition of WIndows in System Properties.
I've noticed with some keys Windows Anytime Upgrade works with Windows 7 but not Windows 7 SP1.